RENR8331-03January 2014

793D Off-Highway TruckHydraulic SystemFDB1-UP

Printed in U.S.A. 2014 Caterpillar, All Rights Reserved

ONE POSITION TWO POSITION THREE POSITION

VENTED PRESSURIZED RETURN ABOVE FLUID LEVEL RETURN BELOW FLUID LEVEL

LINES CROSSING LINES JOINING

TWO - WAY THREE - WAY FOUR - WAY

SPRING CONTROL VALVES RESTRICTION LINE RESTRICTION(FIXED)

PUMP(2 - SECTION)

SPRING(ADJUSTABLE)

VARIABILITY LINE RESTRICTION(VARIABLE)

PRESSURECOMPENSATION

PUMP(VARIABLE & PRESSURE

COMPENSATED)

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

UNIDIRECTIONAL BIDIRECTIONAL

PUSH - PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVE ENVELOPES VALVE PORTS

FLUID CONDITIONERPUMP OR MOTOR

FLUID POWER SYMBOLS

UNIDIRECTIONAL

BIDIRECTIONAL

RELEASED PRESSURE

EXTERNAL RETURN INTERNAL RETURN

REMOTE SUPPLY PRESSURE

SIMPLIFIED

HYDRAULIC PUMPS

ACCUMULATORS

SPRING LOADED GAS CHARGED

SOLENOID OR MANUAL

SOLENOID & PILOT

SOLENOID &PILOT OR MANUAL

SOLENOID SERVO THERMAL DETENT

HYDRAULIC & PNEUMATIC CYLINDERS

DOUBLE ACTINGSINGLE ACTING

BASICSYMBOL

SPRINGLOADED

CHECK VALVES

2 POSITIONINFINITE

POSITIONING

FLOW IN ONEDIRECTION

FLOW INEITHER

DIRECTION

3 POSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMAL POSITION

A B

P T

A B

P TSHIFTED POSITION INFINITE POSITION

CONTROL VALVES

ATTACHMENT

MANUAL SHUTOFF

SHUTTLE PILOTCONTROLLED

MAIN AUX

LINE RESTRICTION(VARIABLE & PRESSURE

COMPENSATED)

MANUAL CONTROL SYMBOLS

HYDRAULIC MOTORS

FLUID STORAGE RESERVOIRS

CROSSING & JOINING LINES

VALVES

PILOT CONTROL SYMBOLS

COMBINATION CONTROLS

BASIC COMPONENT SYMBOLS

ENERGY TRIANGLESHYDRAULIC PNEUMATIC

INTERNALSUPPLY PRESSURE

COMPLETE

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

HYDRAULIC SYMBOLS (ELECTRICAL)

ELECTRICAL SYMBOLS TABLE

325-AG135 PK-14

HARNESS IDENTIFICATION CODE THIS EXAMPLEINDICATES WIRE 135 IN HARNESS AG

325-PK-14

WIRE GAUGE

WIRE COLOR

CIRCUIT NUMBERIDENTIFICATION

WIRE NUMBER IDENTIFICATION CODES

CURRENT STANDARD

PREVIOUS STANDARD

ELECTRICAL SCHEMATIC EXAMPLE HYDRAULIC SCHEMATIC EXAMPLE

325-PK

WIRE COLORCIRCUIT NUMBER

IDENTIFICATION

B

WIRE

WIRE

(EXAMPLE VALVE)

CURRENT STANDARD

TRANSDUCER(FLUID)

MELECTRIC MOTORTRANSDUCER

(GAS / AIR)

G

GENERATOR

PRESSURE SWITCH ELECTRICAL WIREPRESSURE SWITCH(ADJUSTABLE)

TEMPERATURESWITCH

PRESSURESWITCH

TEMPERATURESWITCH

LEVELSWITCH

FLOWSWITCH

ELECTRICAL SYMBOLS (ELECTRICAL)

A

CIRCUIT NUMBERIDENTIFICATION

WIRECOLOR

WIRE GAUGE

T

R

E

N

R

8

3

3

1

-

0

3

3

0

P

a

g

e

,

(

D

i

m

e

n

s

i

o

n

s

:

3

9

i

n

c

h

e

s

x

2

8

i

n

c

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s

)

47

TP7 TP9

TP6

TP8

FAN

STEER

Component Locations Description PartNumber

MachineLocation

SchematicLocation

1

2

456

7

89

1011

1213141516

17

1920

212223242526272829

303132333435

36

Common Rail and Engine Fan

40

41

4344454647

4950

51

52

56575859

616263

646567686970

3

18

Tap LocationsPressure, Sampling, and Sensor

TapNumber Description

SchematicLocation

TP1 Traction Control Valve Right Brake PressTP2 Traction Control Valve Left Brake PressTP3 Steering Pump Discharge Pressure

Manifold PressureSteering Valve Pressure

TP6 Steering Pump Case/ Brake Cooling Motor Case Drains Filter Output Pressure

TP7 Steering Pump Case/ Brake Cooling Motor Case Drains Filter Input Pressure

TP8 Brake Cooling Motor/ Fan Motor Case Drains Filter Output Pressure

TP9 Brake Cooling Motor/ Fan Motor Case Drains Filter Input Pressure

TP10 Parking Brake Pressure (Rear)TP11 Parking Brake Pressure (Front)TP12 Service Brake Pressure, Right , RearTP13 Service Brake Pressure, Left , Rear

Hoist/ Brake Retract Pump PressureHoist/ Brake Retract Pump Pressure

Auto Retaeder Off Pilot PressureAuto Retaeder On Pilot PressureBrake Oil Sampling PressureService Brake Pressure

Description Media Number

Parts Book: SEBP3976

Air System & Brake SOTA RENR8330Steering System RENR8336Fan Drive Hydraulic System RENR8341Traction Control System SENR2986

Schematic RENR8333

Schematic RENR9866Air System:

Related Manuals

Parts Manual:

Machine System:

Electrical System:

MACHINE COMPONENT LOCATIONS

FILTERS BRAKES STEERING

652 64 46 61 40

43

15 20 5 56 3

11 23

50 66

9

13 23

34 26 14 16 17

1922

32

36

31 12 27

58 5235

10 24

36

29 2833 18

45

59

30

25

9 8 21

7

1

57

70

69

4

41244

6

44 47

67

51

68626349

7

TP13TP12

TP11

21

8

22 TP10

28

35 31

13

11

47

35

TP1

TP2

57

7069

44

40

TP5 TP3

44

64

6850

1

59

56

Accumulator Gp - Brake (Charged) 241-3147 E-2

Brake Gp - Serv/Parking (Front), STD Brake Gp - Serv/Parking (Front), XLWS

252-8709188-5020 D-1, E-1

Core As - Oil Clr, (Brk, Hydr.Fan, Strng) 251-4511 D-1Core As - Oil Cooler 253-1807 D-4Core As - Oil Cooler (Front Brakes) 250-6186 D-1

Cylinder Gp - Air/Hydr. (Frnt Serv. Brk) STD: 8W-3406XLWS: 230-9517 E-1

Cylinder Gp - Air/Hydr. (Rear Brake) 8W-3405 E-4Cylinder Gp - Hoist,Telescoping 121-2071 C-2

Filter Gp - Hydr. Oil Cooler 274-7575 D-2Filter Gp - Oil, Service Brakes RearManifold Gp

246-1001186-6317 37

C-4C-4

Plug - Pipe, Orifice 122-7765 F-2Pump and Motor Gp - Brake Release 5T-1060 C-3Pump Gp - Brake Cooling Drive 197-8885 B-4Pump Gp - Hoist And Brake Retract 284-3536 C-4Screen As - Hoist lines 9T-3850 C-4

Screen As - Parking Brake 210-1753 C-438Screen As - Service Brake 6E-5065 F-2

Screen Gp - Hoist Pump 6E-5472 C-4Screen Gp - Hydr. Oil Clr Lines 7J-2656

39D-4

Sensor Gp - Pressure, Parking Brake 221-3410 E-4Slack Adjuster Gp -Front Brakes 205-0559 E-1Slack Adjuster Gp -Rear Brakes 205-0560 E-5Switch Gp - Bypass 164-7577 C-4Switch As - Pressure 117-7773 D-2Tank Gp - Brake 6E-1851 F-2Tank Gp - Hydraulic 267-5592 B-4Valve As - Check 138-4733 D-3Valve and Mtg Gp - Brake (Auto Rtrdr) 177-8840 E-2Valve As - Check 9T-3752

55E-2

Valve As - Check 123-4750 C-3 Valve As - Shuttle 8J-6173 E-1, E-5Valve Gp - Brake 149-4133 E-3Valve Gp - Control (Hoist) 247-1437 D-2Valve Gp - Diverter 105-0170 D-1Valve Gp - Relief 6E-5855 B-4Valve Gp - Traction Control 222-4742 E-4

Wheel Gp - Final Drv / Brk (Rear), STD Wheel Gp - Fnl Drv / Brk (Rear), XLWS

246-5264188-5019 E-5, D-5

Accumulator Gp - Steering 205-0224219-2538 E-7

Adapter 132-6194 D-6Core As 209-7824 42 E-8Core As - Oil Clr (Hydr. Fan, Steering) 199-6683 C-8Cylinders Gp - Steering 9T-8912 E-6Drive Gp - Pump 271-0163 C-6, C-4Filter Element - Hydr. (Steering Oil) 249-2337 B-8Filter Gp - Hydr. Fan, Steering 177-6979 C-8Filter Gp - Rear Axle Oil 192-3841 48 F-8Manifold Gp - Control (RAX Lubrication) 283-5462 E-8Motor Gp - Brake Cooling 198-6041 E-6

Motor Gp - Fan, StandardMotor Gp - Fan, Additional

242-4042240-7790 C-7

Motor Gp - RAX Lube System 202-9940 D-8Motor Gp - Rear Axle Oil Cooler Fan 307-1504 53 E-7Plug As 242-7114 54 E-8Pump Gp - Hydr. Fan 335-5893 C-6Pump Gp - Metering 9T-1318 C-6Pump Gp - Rear Axle Lubrication 214-1555 D-8Pump Gp - Steering 335-5913 C-6Sensor Gp - Pressure 160-1582 60

66E-8

Sensor Gp - Speed, Brk Cooling Pump 186-0131 E-6Switch As - Pressure, High Steering Oil 3E-7812 E-7Switch As - Pressure, Low Steering Oil 3E-7809 E-6Switch Gp - Bypass 164-7577

71F-8

Switch Gp - Pressure, Oil Filter Bypass 253-2673 C-8

Tank and Fliter Gp - Steering 248-6246 B-8Valve Gp - Breaker Relief 117-9152 C-8Valve Gp - Makeup 183-7170 C-7Valve Gp - Sol. and Mnfld Combination 198-6577 E-6Valve Gp - Steer Solenoid And Relief 272-9849 E-7Valve Gp - Steering 9T-8931 D-6

Filter Gp - Hoist Lines 8X-4575 C-4

Screen As - Hydr. Oil Cooler 149-2754 D-2

E-4 E-4

TP4TP5

D-6E-8D-7

C-8

C-8

C-8

C-8

E-5E-1 D-5

Service Brake Pressure, Right , FrontService Brake Pressure, Left , Front

E-5TP14 C-4TP15 C-4TP16 E-2TP17 E-2TP18 E-2TP19 D-2TP20 D-1TP21 E-1

37

38

39

55 71

42485354

60TP4

TP14TP15

TP16

TP17TP19

TP18

TP21

TP20

RE

N

R

8

3

3

1

-

0

3

3

0

P

a

g

e

,

(

D

i

m

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n

s

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:

3

9

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2

8

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Components are shown installed on a fully operable machine with the key and engine off, transmission shifterin neutral and with parking brake set.Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.

SCHEMATIC PART NUMBER: 193-6202, CHANGE: 02, VERSION: -MEDIA NUMBER: RENR8331-03 THIS SCHEMATIC IS FOR THE 793D OFF-HIGHWAY TRUCK HYDRAULIC SYSTEM

Note: Refer to the Parts Manual using a specific serial number prefix in SIS before ordering parts from this schematic.

12345678

A

B

C

D

E

F

12345678

A

B

C

D

E

F

LINE PATTERNS

Drain / Return Lines

Component Group

Pilot / Load Sensing Pressure

Pressure Line

Attachment

Air Line

CALLOUTS

Taps (Pressure, Sampling, Sensor - by letter)YY

HYDRAULIC CIRCUIT COLOR DESCRIPTIONSBRAKE SYSTEM CHARGE PUMP OUTPUT

RAX SYSTEM

HOIST PUMP AND CONTROL CIRCUITSTEERING CIRCUIT

FAN PUMP AND CIRCUIT

SUPPLY LINEPARKING BRAKE CONTROL CIRCUITREAR BRAKE COOLING SYSTEMFRONT BRAKE COOLING SYSTEMDRAIN / RETURN LINESERVICE BRAKES CONTROL CIRCUITSTEERING, RAX FAN, AND BREAK COOLINGMOTOR PUMP OUTPUT

HOIST, BRAKE COOLING, PARKING BRAKE RETRACT AND TRACTION CONTROL SYSTEMS

COMMON RAIL AND ENGINE FAN

TP1

TP13

CL CR

L R

HP

HT

LS EF P T

L R

P T LS

B R CD1 CD2

FULLW2

T1 AUX

EDT2 W1

LOW S

FINALDRIVE DIFFERENTIAL

BANJO HOUSING SUMP

A M G T1 L1

Vg min Vg max

S SL M1 T2 R U

R B

F

T

A SW

P

P

U

M

P

D

R

I

V

E

B

O

X

L1 T1 G M A

Vg max Vg min

U R T2 M1 SL S

HST / BRK TANK LEFTFRONT

LEFTREAR

RIGHTFRONT

RIGHTREAR

LOWER

FLOAT

SNUB

HOLD

RAISE

MAIN RELIEFDUMP SPOOL

P

U

M

P

D

R

I

V

E

B

O

X

BTMR

HS1 HS2 PBS TMS

PBD

BMD HR

RBCO FBCO

RBCR1 FBCR2

RBCR2 FBCR1ECD

M

PUMP GPBRK COOLING

DRIVE197-8885

CYLINDER GPAIR/ HYDR.

FRONT SERV. BRKSTD: 8W-3406

XLWS: 230-9517

TP10

TP2

SWITCH GPBYPASS164-7577 FILTER GP

REAR AXLE OIL192-3841

SENSOR GPPRESSURE

160-1582

CORE AS209-7824

MANIFOLD GPCONTROL(RAXLUBRICATION)283-5462

PLUG AS242-7114

PUMP GPREAR AXLE LUBRICATION

214-1555

MOTOR GPRAX LUBE SYSTEM202-9940

FILTER GPHYDR. FANSTEERING177-6979

VALVE GPBREAKER

RELIEF117-9152

CORE ASOIL COOLERBRAKE/ HYDR. FAN / STEERING199-6683

TANK AND FILTER GPSTEERING248-6246

PUMP GPHYDR. FAN335-5893

MOTOR GPFAN

STANDARD:242-4042

ADDITIONAL:240-7790

VALVE GPMAKEUP183-7170

SWITCH ASPRESSURE

HIGH STEERING OIL3E-7812

ACCUMULATOR GPSTEERING205-0224219-2538 VALVE GP

STEER SOL. / RELIEF272-9849

MOTOR GPFAN

REAR AXLE OIL COOLER307-1504

VALVE GPSOL. AND MANIFOLD COMBINATION198-6577

MOTOR GPBRAKE COOLING

198-6041

SWITCH ASPRESSURELOW STEERING OIL3E-7809

SENSOR GPSPEEDBREAK COOLING PUMP186-0131

CYLINDERS GPSTEERING

9T-8912

VALVE GPSTEERING9T-8931

ADAPTER132-6194

PUMP GPMETERING

9T-1318

DRIVE GPPUMP

271-0163

PUMP GPSTEERING335-5913

WHEEL GPFINAL DRIVE

BREAK , REARSTD : 246-5264

XLWS : 188-5019

WHEEL GPFINAL DRIVE

BREAK , REARSTD : 246-5264

XLWS : 188-5019

SLACK ADJ GP REAR BRAKES

205-0560

VALVE ASSHUTTLE8J-6173

CYLINDER GPAIR/ HYDR. REAR BRK

8W-3405

SENSOR GPPRESSUREPARKING BRAKE221-3410

SENSOR GPPRESSUREPARKING BRAKE221-3410

VALVE GPTRACTION CONTROL222-4742

SCREEN GPHYDR. OILCLR LINES

7J-2656

CORE ASOIL COOLER

253-1807

MANIFOLD GP186-6317

VALVE ASCHECK

138-4733

FILTER GPHOIST LINES

8X-4575DRIVE GP

PUMP271-0163

SCREEN GPHOIST PUMP6E-5472

SWITCH GPBYPASS164-7577

PUMP GPHOIST/

BRK RTRCT284-3536

FILTER GPOIL,SERV BRK, REAR246-1001

SCREEN ASHOIST LINES

9T-3850SCREEN ASPARK BRK210-1753

TANK GPHYDRAULIC

267-5592

VALVE GPRELIEF

6E-5855

VALVE GPRELIEF6E-5855

PUMP AND MOTOR GPBRAKE RELEASE5T-1060

VALVE ASCHECK123-4750

VALVE GPBRAKE

149-4133

PLUG - PIPEORIFICE122-7765

SCREEN ASSERVICE BRAKE

6E-5065

TANK GPBRAKE6E-1851

ACCMLTR GPBRAKE CHARGED

241-3147VALVE AS

CHECK9T-3752 VALVE / MTG GP

BRAKEAUTO RETRDR177-8840

VALVE GPCONTROLHOIST247-1437

SWITCH ASPRESSURE

117-7773

FILTER GPHYDR. OIL

COOLER274-7575

SCREEN ASHYDR. OILCOOLERS149-2754

CYLINDER GPHOIST TELESCOPING121-2071

VALVE GPDIVERTER105-0170

CORE ASOIL CLR

FRONT BRK250-6186

CORE ASOIL CLR

BRK,HYDR. FAN,STEERING251-4511

BRAKE GPSERV./ PARKING

FRONTSTD: 252-8709

XLWS: 188-5020

BRAKE GPSERV./ PARKING

FRONTSTD: 252-8709

XLWS: 188-5020

SLACK ADJ. GPFRONT BRAKES

205-0559

VALVE ASSHUTTLE

8J-6173 TP11

TP7

TP6

TP8

TP9

TP3

TP12

FILTER ELEMENTSHYDR.

STEERING OIL249-2337

SWITCH GPPRESSURE

OIL FILTER BYPASS253-2673

TP4

TP5

TP14 TP15

TP16TP17

TP18

TP19

TP20

TP21